Additional Home Security - Crafted from sturdy alloy, the Door Reinforcement Lock withstands up to 800 lbs of force, 16 times stronger than a normal deadbolt to against being kicked in. Easy to Install - Each Door Reinforcement Lock is equipped with total 8 screws including 4 long and 4 short ones, select the appropriate screws, use an electric drill to install within 5 minutes. Easily add an extra lock to your door. Easy to Use - Use your thumb and forefinger to pinch both the top and bottom grooves, pull to the side and swing away from the door to open the lock. Reverse the actions to close. You can also see a step-by-step instruction in our pictures. Safe to Operate in an Emergency - Upgraded design and high-quality springs allow you to quickly open security door locks and evacuate from the inside. Making Children, Ladies and the Elderly Feel Safer - The sturdy door lock provide extra door lock security for your children, the elderly and ladies when they are at home alone. It also helps preventing children from opening the door to strangers or going out without permission.